New ARC users can access the Italian ARC node computing facilities by requesting a face-2-face visit (ALMA users only, through the ALMA Helpdesk) or by visiting the ARC node in Bologna (for any data-reduction-related issue to be solved in collaboration with the ARC staff).
In both cases, they are requested to send an e-mail to help-desk@alma.inaf.it indicating the reason for the request.

Please notice that the request for a new account for a new requesting user implies that he/she (and/or his/her collaborators) visits the ARC for an introduction on the ARC facilities usage and on issues related to data reduction with CASA both for ALMA or any other telescope. If the request is positively evaluated the visit details will be arranged via e-mail.

The account will guarantee the usage of the facilities and the support for 6 months. Once the account expires the access to the data will be suspended and, after 1 month of quarantine, all data will be removed. Only one gentle reminder will be sent on account of expiration. Extensions of the account duration period could be considered on request (via e-mail). No visit is needed in case of account renewal.

The ARC members support is guaranteed for any ALMA-related issue. For data-reduction-related issues that do not involve ALMA, the support (other than the technical support in the usage of the ARC computing facilities) is limited to the knowledge/experience and availability of the ARC members. The same rules apply also to IRA staff members. IRA collaborators with temporary positions (i.e. students) can have an account for the entire duration of their position.

To ensure a well-balanced load on the cluster nodes please follow instructions about accessing the computer cluster.

Queries can be issued via e-mail to help-desk@alma.inaf.it

Users will be automatically added to the arc-cluster-users@ira.inaf.it mailing list that will be used for any communication from our side.

Once you have obtained an ARC account at IRA, you can access the computer cluster nodes from everywhere through host scheduler.ira.inaf.it.. Using graphical applications on the cluster is possible through remote X access. The accessible working nodes are listed in the table below. You can enter a node for interactive work by typing:

ssh -X ''<node>''.ira.inaf.it

Useful tip: by typing ‘hostname’ you can know on which node you are

The only nodes accessible to almaf2f accounts are 19 and the 22.

Here you can find some statistics about resources consumption on the arcblXX nodes.

You need to change the directory to access your ARC storage on the cluster:

cd /iranet/groups/arc/homesarc/''username'' 

Beware that disks have no redundancy at all, never leave important data on them

Mounting ARC storage on you workstation

• On IRA workstations ARC home filesystem can be accessed on /iranet/homesarc
• On your laptop ARC filesystems can be seamlessly accessed with fuse-sshfs:
• as root, install the package sshfs

# on RedHat/Centos/ScientificLinux
yum install fuse-sshfs
# on Debian/Ubuntu
apt-get install sshfs

then, as user

sshfs storage.alma.inaf.it:/iranet/groups/arc/homesarc/yourhome /your/local/mount/point/

By omitting /remote/path you can mount you home directory.

Be aware that this method is suboptimal for heavy input/output loads. Running disk-intensive applications directly on the arc cluster will result in a file access speed 10-50 times faster.

Software packages available

Software available on ARC cluster could be listed by typing the command setup-help

Computing Nodes

¹ RAM: [A] AMD Ryzen 7 1800X; [B] Intel Xeon E3-1275 v6; [C] Intel Xeon E5-1650 v4;
² SCH.: Scheduler
³ Group: (a) arc-staff, (b) arc-vlbi, (c) arc-f2f, (d) arc-user; Blades are always dedicated to (a) and (b);

Storage Nodes